Detailed investigations on the filamentary structures associated with the type-I edge-localized modes（ELMs） should be helpful for protecting the materials of a plasma-facing wall on a future large device.Related exp...Detailed investigations on the filamentary structures associated with the type-I edge-localized modes（ELMs） should be helpful for protecting the materials of a plasma-facing wall on a future large device.Related experiments have been carefully conducted in the Experimental Advanced Superconducting Tokamak（EAST） using combined Langmuir-magnetic probes.The experimental results indicate that the radially outward velocity of type-I ELMy filaments can be up to 1.7 kms^（-1） in the far scrape-off layer（SOL） region.It is remarkable that the electron temperature of these filaments is detected to be ~50eV,corresponding to a fraction of 1/6 to the temperature near the pedestal top,while the density ~3×10^（19）m^（-3） of these filaments could be approximate to the line-averaged density.In addition,associated magnetic fluctuations have been clearly observed at the same time,which show good agreement with the density perturbations.A localized current on the order of ~100kA could be estimated within the filaments.展开更多
We experimentally demonstrate a long-term stable two-dimensional saturable absorption material under ambient conditions—multi-layer antimonene feasible for the mid-infrared spectral region—for the first time to our ...We experimentally demonstrate a long-term stable two-dimensional saturable absorption material under ambient conditions—multi-layer antimonene feasible for the mid-infrared spectral region—for the first time to our knowledge. The multi-layer antimonene material prepared using a liquid-phase exfoliation method was coated on a quartz/Ca F_2 for characterizations and an Au mirror as a reflection-type saturable absorber(SA) device. It has a modulation depth of 10.5%, a saturation peak intensity of 0.26 GW∕cm^2, and a non-saturation loss of 19.1% measured at 2868.0 nm using the typical power-dependent method. By introducing the SA device into a linear-cavity Ho^(3+)∕ Pr^(3+)-codoped fluoride fiber laser at 2865.0 nm, stable Q-switched pulses were obtained. It generated a maximum output power of 112.3 m W and pulse energy of 0.72 μJ, while the shortest pulse duration and largest repetition rate were 1.74 μs and 156.2 k Hz, respectively. The long-term stability of the SA device was also checked using the same laser setup within 28 days. The results indicate that multi-layer antimonene is a type of promising long-term stable SA material under ambient conditions that can be applied in the mid-infrared spectral region.展开更多
基金supported by National Natural Science Foundation of China under Contracts Nos.11275047,11705128,11422546,11575235,11575236 and 11505222Key Research Program of Frontier Sciences,CAS,Grant No.QYZDB-SSWSLH001National Magnetic Confinement Fusion Science Program of China under Contract Nos.2015GB101000 and 2013GB107003
文摘Detailed investigations on the filamentary structures associated with the type-I edge-localized modes（ELMs） should be helpful for protecting the materials of a plasma-facing wall on a future large device.Related experiments have been carefully conducted in the Experimental Advanced Superconducting Tokamak（EAST） using combined Langmuir-magnetic probes.The experimental results indicate that the radially outward velocity of type-I ELMy filaments can be up to 1.7 kms^（-1） in the far scrape-off layer（SOL） region.It is remarkable that the electron temperature of these filaments is detected to be ~50eV,corresponding to a fraction of 1/6 to the temperature near the pedestal top,while the density ~3×10^（19）m^（-3） of these filaments could be approximate to the line-averaged density.In addition,associated magnetic fluctuations have been clearly observed at the same time,which show good agreement with the density perturbations.A localized current on the order of ~100kA could be estimated within the filaments.
基金National Natural Science Foundation of China(NSFC)(61722503,61435003,61421002)Open Fund of Science and Technology on Solid-State Laser Laboratory+3 种基金Fundamental Research Funds for the Central Universities(ZYGX2016J068)International Scientific Cooperation Project of Sichuan Province(2017HH0046)National Key R&D Program of China(YS2018YFB110012)Natural Science Foundation of Zhejiang Province(LQ18A040004)
文摘We experimentally demonstrate a long-term stable two-dimensional saturable absorption material under ambient conditions—multi-layer antimonene feasible for the mid-infrared spectral region—for the first time to our knowledge. The multi-layer antimonene material prepared using a liquid-phase exfoliation method was coated on a quartz/Ca F_2 for characterizations and an Au mirror as a reflection-type saturable absorber(SA) device. It has a modulation depth of 10.5%, a saturation peak intensity of 0.26 GW∕cm^2, and a non-saturation loss of 19.1% measured at 2868.0 nm using the typical power-dependent method. By introducing the SA device into a linear-cavity Ho^(3+)∕ Pr^(3+)-codoped fluoride fiber laser at 2865.0 nm, stable Q-switched pulses were obtained. It generated a maximum output power of 112.3 m W and pulse energy of 0.72 μJ, while the shortest pulse duration and largest repetition rate were 1.74 μs and 156.2 k Hz, respectively. The long-term stability of the SA device was also checked using the same laser setup within 28 days. The results indicate that multi-layer antimonene is a type of promising long-term stable SA material under ambient conditions that can be applied in the mid-infrared spectral region.
